Sir Hans Adolf Krebs,
FRS (, ; 25 August 1900 – 22 November 1981)
was a German-born British
biologist
A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual Cell (biology), cell, a multicellular organism, or a Community (ecology), community of Biological inter ...
,
physician
A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...
and
biochemist
Biochemists are scientists who are trained in biochemistry. They study chemical processes and chemical transformations in living organisms. Biochemists study DNA, proteins and Cell (biology), cell parts. The word "biochemist" is a portmanteau of ...
. He was a pioneer scientist in the study of
cellular respiration
Cellular respiration is the process by which biological fuels are oxidised in the presence of an inorganic electron acceptor such as oxygen to produce large amounts of energy, to drive the bulk production of ATP. Cellular respiration may be des ...
, a biochemical process in
living cells
The cell is the basic structural and functional unit of life forms. Every cell consists of a cytoplasm enclosed within a membrane, and contains many biomolecules such as proteins, DNA and RNA, as well as many small molecules of nutrients an ...
that extracts energy from food and
oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...
and makes it available to drive the processes of life. He is best known for his discoveries of two important sequences of chemical reactions that take place in the cells of humans and many other
organism
In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...
s, namely the
citric acid cycle
The citric acid cycle (CAC)—also known as the Krebs cycle or the TCA cycle (tricarboxylic acid cycle)—is a series of chemical reactions to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins ...
and the
urea cycle
The urea cycle (also known as the ornithine cycle) is a cycle of biochemical reactions that produces urea (NH2)2CO from ammonia (NH3). Animals that use this cycle, mainly amphibians and mammals, are called ureotelic.
The urea cycle converts highl ...
. The former, often eponymously known as the "Krebs cycle", is the key sequence of metabolic reactions that provides energy in the cells of humans and other
oxygen-respiring organisms; and its discovery earned Krebs a
Nobel Prize in Physiology or Medicine
The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, accord ...
in 1953. With
Hans Kornberg
Sir Hans Leo Kornberg, FRS (14 January 1928 – 16 December 2019) was a British-American biochemist. He was Sir William Dunn Professor of Biochemistry in the University of Cambridge from 1975 to 1995, and Master of Christ's College, Cambridge ...
, he also discovered the
glyoxylate cycle
The glyoxylate cycle, a variation of the tricarboxylic acid cycle, is an anabolic pathway occurring in plants, bacteria, protists, and fungi. The glyoxylate cycle centers on the conversion of acetyl-CoA to succinate for the synthesis of carbohydrat ...
, which is a slight variation of the citric acid cycle found in plants,
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among ...
,
protists
A protist () is any eukaryotic organism (that is, an organism whose cells contain a cell nucleus) that is not an animal, plant, or fungus. While it is likely that protists share a common ancestor (the last eukaryotic common ancestor), the excl ...
, and fungi.
Krebs died in 1981 in
Oxford
Oxford () is a city in England. It is the county town and only city of Oxfordshire. In 2020, its population was estimated at 151,584. It is north-west of London, south-east of Birmingham and north-east of Bristol. The city is home to the ...
, where he had spent 13 years of his career from 1954 until his retirement in 1967 at the
University of Oxford
, mottoeng = The Lord is my light
, established =
, endowment = £6.1 billion (including colleges) (2019)
, budget = £2.145 billion (2019–20)
, chancellor ...
.
Biography
Early life and education
Krebs was born in
Hildesheim
Hildesheim (; nds, Hilmessen, Hilmssen; la, Hildesia) is a city in Lower Saxony, Germany with 101,693 inhabitants. It is in the district of Hildesheim, about southeast of Hanover on the banks of the Innerste River, a small tributary of the Lei ...
, Germany, to Georg Krebs, an
ear, nose, and throat
Otorhinolaryngology ( , abbreviated ORL and also known as otolaryngology, otolaryngology–head and neck surgery (ORL–H&N or OHNS), or ear, nose, and throat (ENT)) is a surgical subspeciality within medicine that deals with the surgical a ...
surgeon, and Alma Krebs (née Davidson). He descended from Jewish-Silesian ancestry and was the middle of three children, older sister Elisabeth and younger brother Wolfgang.
Krebs attended the famous old Gymnasium Andreanum in his home town. Near the end of
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
, in September 1918, six months short of completing his secondary school education, he was
conscripted
Conscription (also called the draft in the United States) is the state-mandated enlistment of people in a national service, mainly a military service. Conscription dates back to antiquity and it continues in some countries to the present day un ...
into the
Imperial German Army
The Imperial German Army (1871–1919), officially referred to as the German Army (german: Deutsches Heer), was the unified ground and air force of the German Empire. It was established in 1871 with the political unification of Germany under the l ...
. He was allowed to take an emergency examination for his high school diploma, which he passed with such a high score that he suspected the examiners of being "unduly lenient and sympathetic". With the end of the war two months later, his conscription ended.
Krebs decided to follow his father's profession and entered the
University of Göttingen
The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...
in December 1918 to study medicine. In 1919 he transferred to the
University of Freiburg
The University of Freiburg (colloquially german: Uni Freiburg), officially the Albert Ludwig University of Freiburg (german: Albert-Ludwigs-Universität Freiburg), is a public university, public research university located in Freiburg im Breisg ...
. In 1923 he published his first scientific paper on a
tissue staining technique. He did this work under the guidance of Wilhelm von Mollendorf starting it in 1920. He completed his medical course in December 1923. To obtain a
Doctor of Medicine
Doctor of Medicine (abbreviated M.D., from the Latin language, Latin ''Medicinae Doctor'') is a medical degree, the meaning of which varies between different jurisdictions. In the United States, and some other countries, the M.D. denotes a profes ...
degree, and a medical license, he spent one year at the Third Medical Clinic in the
University of Berlin
Humboldt-Universität zu Berlin (german: Humboldt-Universität zu Berlin, abbreviated HU Berlin) is a German public research university in the central borough of Mitte in Berlin. It was established by Frederick William III on the initiative o ...
. By then he had turned his professional goal from becoming a practising physician to becoming a medical researcher, particularly in biochemistry. In 1924 he studied at the Department of Chemistry at the Pathological Institute of the
Charité
The Charité – Universitätsmedizin Berlin (Charité – Berlin University of Medicine) is one of Europe's largest university hospitals, affiliated with Humboldt University and Free University Berlin. With numerous Collaborative Research Cen ...
Hospital, in
Berlin
Berlin ( , ) is the capital and largest city of Germany by both area and population. Its 3.7 million inhabitants make it the European Union's most populous city, according to population within city limits. One of Germany's sixteen constitue ...
, for training in chemistry and biochemistry. He earned his
MD degree in 1925 from the
University of Hamburg
The University of Hamburg (german: link=no, Universität Hamburg, also referred to as UHH) is a public research university in Hamburg, Germany. It was founded on 28 March 1919 by combining the previous General Lecture System ('' Allgemeines Vor ...
.
Career
In 1926 Krebs joined
Otto Heinrich Warburg
Otto Heinrich Warburg (, ; 8 October 1883 – 1 August 1970), son of physicist Emil Warburg, was a German physiologist, medical doctor, and Nobel laureate. He served as an officer in the elite Uhlan (cavalry regiment) during the First World War ...
as a research assistant at the
Kaiser Wilhelm Institute for Biology in
Dahlem, Berlin
Dahlem ( or ) is a locality of the Steglitz-Zehlendorf borough in southwestern Berlin. Until Berlin's 2001 administrative reform it was a part of the former borough of Zehlendorf, Berlin, Zehlendorf. It is located between the mansion settlements ...
. He was paid a modest 4800
marks
Marks may refer to:
Business
* Mark's, a Canadian retail chain
* Marks & Spencer, a British retail chain
* Collective trade marks, trademarks owned by an organisation for the benefit of its members
* Marks & Co, the inspiration for the novel '' ...
per year. After four years in 1930, with 16 publications to his credit, his mentor Warburg urged him to move on and he took up the position of Assistant in the Department of Medicine at the Municipal Hospital in
Altona (now part of
Hamburg
(male), (female) en, Hamburger(s),
Hamburgian(s)
, timezone1 = Central (CET)
, utc_offset1 = +1
, timezone1_DST = Central (CEST)
, utc_offset1_DST = +2
, postal ...
). The next year he moved to the Medical Clinic of the
University of Freiburg
The University of Freiburg (colloquially german: Uni Freiburg), officially the Albert Ludwig University of Freiburg (german: Albert-Ludwigs-Universität Freiburg), is a public university, public research university located in Freiburg im Breisg ...
. At Freiburg he was in charge of about 40 patients, and was at liberty to do his own research. Before a year was over at Freiburg, he, with research student
Kurt Henseleit
Kurt Henseleit (1907–1973) studied medicine in Berlin, where he was born, with final exams 1929 and was beginning in the winter semester 1930/31 a graduate student of and assistant to Hans Krebs in Freiburg im Breisgau, where he got his M.D. Be ...
, published their discovery of the ornithine cycle of urea synthesis, which is the metabolic pathway for
urea
Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid.
Urea serves an important r ...
formation. It is now known as the
urea cycle
The urea cycle (also known as the ornithine cycle) is a cycle of biochemical reactions that produces urea (NH2)2CO from ammonia (NH3). Animals that use this cycle, mainly amphibians and mammals, are called ureotelic.
The urea cycle converts highl ...
, and is sometimes also referred to as the Krebs–Henseleit cycle. Together they also developed a complex
aqueous solution
An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, or sodium chloride (NaCl), in water would be re ...
(a
buffer
Buffer may refer to:
Science
* Buffer gas, an inert or nonflammable gas
* Buffer solution, a solution used to prevent changes in pH
* Buffering agent, the weak acid or base in a buffer solution
* Lysis buffer, in cell biology
* Metal ion buffer
* ...
), or
perfusion
Perfusion is the passage of fluid through the circulatory system or lymphatic system to an organ or a tissue, usually referring to the delivery of blood to a capillary bed in tissue. Perfusion is measured as the rate at which blood is deliver ...
''ex vivo'', for studying blood flow in arteries, which is now called the Krebs–Henseleit buffer.) In 1932 he published the basic chemical reactions of the urea cycle, which established his scientific reputation.
Krebs's life as a respected German scientist came to an abrupt halt in 1933 because of his Jewish ancestry. With the rise of
Hitler
Adolf Hitler (; 20 April 188930 April 1945) was an Austrian-born German politician who was dictator of Germany from 1933 until his death in 1945. He rose to power as the leader of the Nazi Party, becoming the chancellor in 1933 and then ...
's
Nazi Party
The Nazi Party, officially the National Socialist German Workers' Party (german: Nationalsozialistische Deutsche Arbeiterpartei or NSDAP), was a far-right politics, far-right political party in Germany active between 1920 and 1945 that crea ...
to power, Germany decreed the
Law for the Restoration of the Professional Civil Service
The Law for the Restoration of the Professional Hitler Service (german: Gesetz zur Wiederherstellung des Berufsbeamtentums, shortened to ''Berufsbeamtengesetz''), also known as Civil Service Law, Civil Service Restoration Act, and Law to Re-es ...
, which decreed the removal of all non-Germans, and anti-Nazis, from professional occupations. Krebs received his official dismissal from his job in April 1933, and his service was terminated on 1 July 1933. An admirer,
Sir Frederick Gowland Hopkins
Sir Frederick Gowland Hopkins (20 June 1861 – 16 May 1947) was an English biochemist who was awarded the Nobel Prize in Physiology or Medicine in 1929, with Christiaan Eijkman, for the discovery of vitamins, even though Casimir Funk, a P ...
at the
University of Cambridge
, mottoeng = Literal: From here, light and sacred draughts.
Non literal: From this place, we gain enlightenment and precious knowledge.
, established =
, other_name = The Chancellor, Masters and Schola ...
, immediately came to his rescue, and persuaded the university to recruit Krebs to work with him in the Department of Biochemistry. By July 1933 he was settled in Cambridge with financial support from the
Rockefeller Foundation
The Rockefeller Foundation is an American private foundation and philanthropic medical research and arts funding organization based at 420 Fifth Avenue, New York City. The second-oldest major philanthropic institution in America, after the Carneg ...
.
Although Germany restricted him to bringing only his personal belongings, he was fortunate that the government agents allowed him to take his equipment and research samples to England. They proved to be pivotal to his later discoveries, especially the
manometer
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressur ...
developed by Warburg specifically for the measurement of oxygen consumption in thin slices of tissues; it was the basis for his research.
He was appointed as Demonstrator in biochemistry in 1934 and in 1935 the
University of Sheffield
, mottoeng = To discover the causes of things
, established = – University of SheffieldPredecessor institutions:
– Sheffield Medical School – Firth College – Sheffield Technical School – University College of Sheffield
, type = Pu ...
offered him a post of Lecturer in Pharmacology, with a more spacious laboratory and double the salary. He worked there for 19 years. The University of Sheffield opened a Department of Biochemistry, now Department of Molecular Biology and Biotechnology, in 1938 and Krebs became its first Head, and eventually a Professor in 1945. Krebs took over the running of the
Sorby Research Institute
The Sorby Research Institute was a research facility that operated in the UK during and immediately after the Second World War in Sheffield, England. The Institute mostly investigated questions of nutrition. This was an important consideration i ...
in 1943. In 1944, the British
Medical Research Council established the MRC Unit for Cell Metabolism Research at Sheffield, and Krebs was appointed the Director. With this his laboratory became so large that the locals jokingly nicknamed it "Krebs's Empire".
He moved with his MRC unit to the
University of Oxford
, mottoeng = The Lord is my light
, established =
, endowment = £6.1 billion (including colleges) (2019)
, budget = £2.145 billion (2019–20)
, chancellor ...
in 1954 as
Whitley Professor of Biochemistry
The position of Whitley Professor of Biochemistry at the University of Oxford is one of the permanent chairs of the university, and the first in the field of biochemistry at the university. It is associated with a fellowship at Trinity College, Oxf ...
, the post he held till his retirement in 1967. The editorial board of ''
Biochemical Journal
The ''Biochemical Journal'' is a peer-reviewed scientific journal which covers all aspects of biochemistry, as well as cell and molecular biology. It is published by Portland Press and was established in 1906.
History
The journal was established i ...
'' extended their good wishes on his retirement, but in return he promised to keep them busy, by producing scientific papers. He continued his research, and took his MRC unit to the Nuffield Department of Clinical Medicine at the
Radcliffe Infirmary
The Radcliffe Infirmary was a hospital in central north Oxford, England, located at the southern end of Woodstock Road on the western side, backing onto Walton Street.
History
The initial proposals to build a hospital in Oxford were put forw ...
, Oxford. From there he published over 100 research papers.
[
]
Personal life and death
Krebs met Margaret Cicely Fieldhouse (30 October 1913 – May 1993) when he moved to Sheffield in 1935. They married on 22 March 1938. Krebs later described his life in Sheffield as "19 happy years".[ They had two sons, Paul (born 1939) and John (born 1945), and a daughter, Helen (born 1942). John ( Sir John Krebs, and later Baron Krebs) became a renowned ]ornithologist
Ornithology is a branch of zoology that concerns the "methodological study and consequent knowledge of birds with all that relates to them." Several aspects of ornithology differ from related disciplines, due partly to the high visibility and th ...
, Professor at the University of Oxford, Principal of Jesus College, Oxford
Jesus College (in full: Jesus College in the University of Oxford of Queen Elizabeth's Foundation) is one of the constituent colleges of the University of Oxford in England. It is in the centre of the city, on a site between Turl Street, Ship St ...
, and Member of the British House of Lords.
After a brief illness, Krebs died on 22 November 1981 in Oxford, aged 81.[
]
Achievements
Urea cycle (Krebs–Henseleit cycle)
In 1932 Krebs worked out the outlines of the urea cycle with a medical student Kurt Henseleit at the university of Freiburg. While working at the Medical Clinic of the University of Freiburg, Krebs met Kurt Henseleit
Kurt Henseleit (1907–1973) studied medicine in Berlin, where he was born, with final exams 1929 and was beginning in the winter semester 1930/31 a graduate student of and assistant to Hans Krebs in Freiburg im Breisgau, where he got his M.D. Be ...
, with whom he investigated the chemical process of urea
Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid.
Urea serves an important r ...
formation. In 1904, two Germans A. Kossel and H. D. Dakin had shown that arginine
Arginine is the amino acid with the formula (H2N)(HN)CN(H)(CH2)3CH(NH2)CO2H. The molecule features a guanidino group appended to a standard amino acid framework. At physiological pH, the carboxylic acid is deprotonated (−CO2−) and both the am ...
could be hydrolysed by the enzyme arginase
Arginase (, ''arginine amidinase'', ''canavanase'', ''L-arginase'', ''arginine transamidinase'') is a manganese-containing enzyme. The reaction catalyzed by this enzyme is:
: arginine + H2O → ornithine + urea
It is the final enzyme of the ure ...
to form ornithine
Ornithine is a non-proteinogenic amino acid that plays a role in the urea cycle. Ornithine is abnormally accumulated in the body in ornithine transcarbamylase deficiency. The radical is ornithyl.
Role in urea cycle
L-Ornithine is one of the produ ...
and urea in inorganic reaction. Based on this reaction, Krebs and Henseleit postulated that in living cells, similar reaction could occur, and that ornithine and citrulline
The organic compound citrulline is an α-amino acid. Its name is derived from ''citrullus'', the Latin word for watermelon. Although named and described by gastroenterologists since the late 19th century, it was first isolated from watermelon in 1 ...
could be the intermediate reactions. Krebs started working on the possible method for the synthesis of arginine. Using his Warburg manometer, he mixed a slice of liver with purified ornithine and citrulline. He found that citrulline acted as a catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...
in the metabolic reactions of urea from ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...
and carbon dioxide
Carbon dioxide (chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is transpar ...
. He and Henseleit published their discovery in 1932. Thus the urea cycle
The urea cycle (also known as the ornithine cycle) is a cycle of biochemical reactions that produces urea (NH2)2CO from ammonia (NH3). Animals that use this cycle, mainly amphibians and mammals, are called ureotelic.
The urea cycle converts highl ...
(or "ornithine cycle") was established, and it was the first metabolic cycle to be discovered.[
]
Citric acid cycle (Krebs cycle)
At the University of Sheffield, Krebs and William Johnson investigated cellular respiration by which oxygen was consumed to produce energy from the breakdown of glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using ...
. Krebs had earlier suggested to Warburg while they worked together in Germany that by using a manometer
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressur ...
it could be possible to detect the oxygen consumption and identify the chemical reaction in glucose metabolism
Carbohydrate metabolism is the whole of the biochemical processes responsible for the metabolic formation, breakdown, and interconversion of carbohydrates in living organisms.
Carbohydrates are central to many essential metabolic pathways. Plants ...
. Warburg had flatly rejected the idea. In Sheffield Krebs vigorously worked to identify a possible chemical reaction and came up with numerous hypothetical pathways. Using the manometer he tested those hypotheses one by one. One hypothesis involving succinate
Succinic acid () is a dicarboxylic acid with the chemical formula (CH2)2(CO2H)2. The name derives from Latin ''succinum'', meaning amber. In living organisms, succinic acid takes the form of an anion, succinate, which has multiple biological ro ...
, fumarate
Fumaric acid is an organic compound with the formula HO2CCH=CHCO2H. A white solid, fumaric acid occurs widely in nature. It has a fruit-like taste and has been used as a food additive. Its E number is E297.
The salts and esters are known as f ...
, and malate
Malic acid is an organic compound with the molecular formula . It is a dicarboxylic acid that is made by all living organisms, contributes to the sour taste of fruits, and is used as a food additive. Malic acid has two stereoisomeric forms (L ...
proved to be useful because all these molecules increased oxygen consumption in the pigeon breast muscle. In 1937 German biochemists Franz Koop and Carl Martinus had demonstrated a series of reactions using citrate
Citric acid is an organic compound with the chemical formula HOC(CO2H)(CH2CO2H)2. It is a colorless weak organic acid. It occurs naturally in citrus fruits. In biochemistry, it is an intermediate in the citric acid cycle, which occurs in t ...
that produced oxaloacetate
Oxaloacetic acid (also known as oxalacetic acid or OAA) is a crystalline organic compound with the chemical formula HO2CC(O)CH2CO2H. Oxaloacetic acid, in the form of its conjugate base oxaloacetate, is a metabolic intermediate in many processes ...
. Krebs realised that these molecules could be the missing intermediates for such reaction. After four months of experimental works to fill in the gaps, Krebs and Johnson succeeded in establishing the sequence of the chemical cycle, which they called the "citric acid cycle
The citric acid cycle (CAC)—also known as the Krebs cycle or the TCA cycle (tricarboxylic acid cycle)—is a series of chemical reactions to release stored energy through the oxidation of acetyl-CoA derived from carbohydrates, fats, and proteins ...
". It is also known as the "Krebs cycle" or "tricarboxylic acid (TCA) cycle".
Krebs sent a short manuscript account of the discovery to ''Nature
Nature, in the broadest sense, is the physics, physical world or universe. "Nature" can refer to the phenomenon, phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. ...
'' on 10 June 1937. On 14 June he received a rejection letter from the editor, saying that the journal had "already sufficient letters to fill correspondence columns for seven or eight weeks", and encouraging Krebs to "submit it for early publication to another periodical." Krebs immediately prepared a longer version titled "The Role of Citric Acid in Intermediate Metabolism in Animal Tissues", which he sent to the Dutch journal '' Enzymologia'' after two weeks and was published in two months.[ It was followed by a series of papers in different journals.
]
Glyoxylate cycle
Krebs continued to add more details to his citric acid cycle. The discovery of acetyl-CoA
Acetyl-CoA (acetyl coenzyme A) is a molecule that participates in many biochemical reactions in protein, carbohydrate and lipid metabolism. Its main function is to deliver the acetyl group to the citric acid cycle (Krebs cycle) to be oxidized for ...
in 1947 by Fritz Albert Lipmann
Fritz Albert Lipmann (; June 12, 1899 – July 24, 1986) was a German-American biochemist and a co-discoverer in 1945 of coenzyme A. For this, together with other research on coenzyme A, he was awarded the Nobel Prize in Physiology or Medicine in ...
was another major contribution.[ However, this new discovery posed a problem in his classic reaction. In 1957 he, with ]Hans Kornberg
Sir Hans Leo Kornberg, FRS (14 January 1928 – 16 December 2019) was a British-American biochemist. He was Sir William Dunn Professor of Biochemistry in the University of Cambridge from 1975 to 1995, and Master of Christ's College, Cambridge ...
, found that there were additional crucial enzymes. One was malate synthase
In enzymology, a malate synthase () is an enzyme that catalyzes the chemical reaction
:acetyl-CoA + H2O + glyoxylate \rightarrow (''S'')-malate + CoA
The 3 substrates of this enzyme are acetyl-CoA, H2O, and glyoxylate, whereas its two products ...
, which condenses acetate with glyoxylate to form malate, and the other was isocitrate lyase
Isocitrate lyase (), or ICL, is an enzyme in the glyoxylate cycle that catalyzes the cleavage of isocitrate to succinate and glyoxylate. Together with malate synthase, it bypasses the two decarboxylation steps of the tricarboxylic acid cycle (TC ...
, which provides glyoxylate for the reaction by cleaving it from isocitrate. These two reactions did not follow the normal citric acid cycle, and hence the pathway was named the glyoxylate bypass of the citric acid cycle, but is now known as the glyoxylate cycle
The glyoxylate cycle, a variation of the tricarboxylic acid cycle, is an anabolic pathway occurring in plants, bacteria, protists, and fungi. The glyoxylate cycle centers on the conversion of acetyl-CoA to succinate for the synthesis of carbohydrat ...
.[
]
Honours and awards
Krebs became a naturalised British citizen
British nationality law prescribes the conditions under which a person is recognised as being a national of the United Kingdom. The six different classes of British nationality each have varying degrees of civil and political rights, due to the ...
in 1939. He was elected Fellow of Trinity College Trinity College may refer to:
Australia
* Trinity Anglican College, an Anglican coeducational primary and secondary school in , New South Wales
* Trinity Catholic College, Auburn, a coeducational school in the inner-western suburbs of Sydney, New ...
, Oxford, 1954–1967. He was elected to the Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, re ...
in 1947. In 1953 he received the Nobel Prize in Physiology or Medicine
The Nobel Prize in Physiology or Medicine is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, accord ...
for his "discovery of the citric acid cycle." (He shared the Nobel Prize with Fritz Lipmann
Fritz Albert Lipmann (; June 12, 1899 – July 24, 1986) was a German-American biochemist and a co-discoverer in 1945 of coenzyme A. For this, together with other research on coenzyme A, he was awarded the Nobel Prize in Physiology or Medicine in ...
.) For the same reason he was given the Albert Lasker Award for Basic Medical Research
The Albert Lasker Award for Basic Medical Research is one of the prizes awarded by the Lasker Foundation for a fundamental discovery that opens up a new area of biomedical science. The award frequently precedes a Nobel Prize in Medicine; almost 5 ...
in 1953. The Royal Society awarded him its Royal Medal
The Royal Medal, also known as The Queen's Medal and The King's Medal (depending on the gender of the monarch at the time of the award), is a silver-gilt medal, of which three are awarded each year by the Royal Society, two for "the most important ...
in 1954, and Copley Medal
The Copley Medal is an award given by the Royal Society, for "outstanding achievements in research in any branch of science". It alternates between the physical sciences or mathematics and the biological sciences. Given every year, the medal is t ...
in 1961. He was elected to the American Academy of Arts and Sciences
The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and ...
in 1957. In 1958 he received the Gold Medal of the Netherlands Society for Physics, Medical Science and Surgery. He was knighted in 1958 and was elected Honorary Fellow of Girton College
Girton College is one of the Colleges of the University of Cambridge, 31 constituent colleges of the University of Cambridge. The college was established in 1869 by Emily Davies and Barbara Bodichon as the first women's college in Cambridge. In 1 ...
, Cambridge University
, mottoeng = Literal: From here, light and sacred draughts.
Non literal: From this place, we gain enlightenment and precious knowledge.
, established =
, other_name = The Chancellor, Masters and Schola ...
, in 1979. He was the Original Member of the Society for General Microbiology
The Microbiology Society (previously the Society for General Microbiology) is a learned society based in the United Kingdom with a worldwide membership based in universities, industry, hospitals, research institutes and schools. It is the large ...
, which conferred him Honorary Membership in 1980. He was also an elected member of both the American Philosophical Society
The American Philosophical Society (APS), founded in 1743 in Philadelphia, is a scholarly organization that promotes knowledge in the sciences and humanities through research, professional meetings, publications, library resources, and communit ...
and the United States National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...
. He received an honorary doctorate from 21 universities.
In July 2015, Krebs's Nobel Prize medal was auctioned off for £225,000 (around $351,225). The proceeds were used to found the Sir Hans Krebs Trust, which provides funding for doctoral students in the biomedical field and support chemists who had to flee their home countries.
Legacy
The University of Oxford had a building named Hans Krebs Tower, which was occupied by the Department of Biochemistry. In 2008 a new building for the Department of Biochemistry was constructed, on which a plaque was placed on 20 May 2013 by the Association of Jewish Refugees
The Association of Jewish Refugees (AJR) is the specialist nationwide social and welfare services charity representing and supporting Jewish victims of Nazi oppression, and their dependants and descendants, living in Great Britain. The AJR celebra ...
. The plaque was unveiled by John, Lord Krebs, and the inscription reads:
The University of Sheffield has The Krebs Institute, founded in 1988. It is a research centre covering interdisciplinary programmes in biochemical research.
In 1990 the Federation of European Biochemical Societies The Federation of the European Biochemical Societies, frequently abbreviated FEBS, is an international scientific society promoting activities in biochemistry, molecular biology and related research areas in Europe and neighbouring regions. It was f ...
instituted the Sir Hans Krebs Lecture and Medal, which was endowed by the Lord Rank Centre for Research. It is awarded for outstanding achievements in biochemistry and molecular biology.
The Society of Friends of Hannover Medical School
The Hannover Medical SchoolAlthough the English spelling of the city name is "Hanover", this form of the name, using the German spelling of the city name, is used as the English-language name of the school, for example . (german: Medizinische Ho ...
gives the Sir Hans Krebs Prize, which is worth 10,000 euros.
The Biochemical Society
The Biochemical Society is a learned society in the United Kingdom in the field of biochemistry, including all the cellular and molecular biosciences.
Structure
It currently has around 7000 members, two-thirds in the UK. It is affiliated with th ...
offers Krebs Memorial Scholarship to a postgraduate (PhD) student working in biochemistry or an allied biomedical science at any British university. As of 2014, the scholarship is worth £18,500 and is given for a year, but is extendable up to three years.
See also
*List of Jewish Nobel laureates
Nobel Prizes have been awarded to over 900 individuals, of whom at least 20% were Jews.
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The number of Jews receiving Nobel prizes has been the subject of some attention.*
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*"Jews rank high among winners of Nobel, but why ...
*List of refugees
This is a list of prominent people who fled their native country, went into exile and found refuge in another country. The list follows the current legal concept of refugee only loosely. It also includes children of people who have fled. The peopl ...
References
Bibliography
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External links
* including the Nobel Lecture, 11 December 1953 ''The Citric Acid Cycle''
1953 Prize in Physiology or Medicine
Nobel Prizes
Deconstructing the Tour, University of Sheffield (biography)
Catalogue of the papers and correspondence of SIR HANS ADOLF KREBS, FRS (1900–1981)
Hans A. Krebs
Nobel Luminaries – Jewish Nobel Prize Winners, on th
Beit Hatfutsot-The Museum of the Jewish People
Website.
{{DEFAULTSORT:Krebs, Hans Adolf
1900 births
1981 deaths
Nobel laureates in Physiology or Medicine
British Nobel laureates
German Nobel laureates
Academics of the University of Cambridge
Academics of the University of Sheffield
British biochemists
German biochemists
Fellows of Girton College, Cambridge
Fellows of the Royal Society
Foreign associates of the National Academy of Sciences
Jewish chemists
Jewish scientists
Jewish emigrants from Nazi Germany to the United Kingdom
Naturalised citizens of the United Kingdom
People from Hildesheim
Humboldt University of Berlin alumni
People from the Province of Hanover
Recipients of the Albert Lasker Award for Basic Medical Research
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Recipients of the Pour le Mérite (civil class)
Royal Medal winners
University of Freiburg alumni
University of Freiburg faculty
Physicians of the Charité
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Ludwig Maximilian University of Munich alumni
German emigrants to England
Knights Bachelor
Whitley Professors of Biochemistry
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